摘 要: | REE. determinations were conducted f or their fractional contents on granitoid rocks in South China, which differ in age, composition and origin by means of chemical-X-ray fluorescence spectrometry and instruments! neutron activation analysis technique. Granites under consideration can be divided into three major categories in terms of normalized REE distribution pattern of ehondrite and δEu value: 1. REE distribution pattern is approximately expressed by a smooth eurve,with unremarkable negative Eu anomaly and δEu value greater than 0.5; 2. REE distribution pattern exhibits a moderately remarkable negative Eu anomaly with δEu value in the range of 0.3---0.4; 3. REE distribution pattern gives a greatly remarkable .negative Eu anomaly,with δEu value being less than 0.2. The granites belonging to the first category are mostly older in age and closely connected with geanitization in origin, those to the second category show a number of evidences for their magmatic origin anti those to the third category are especially distinquishable for their characteristic features of later maginatio differentiation and replacement.
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